Do those drug free school zones mean anything?

Do the drug free school zones mean anything extra from a law enforcement perspective? We have a neighbor issue who is on medical weed and I don't care what people believe even if you have a medical card it is still illegal under federal law. We are also recently moved into this home as a rent to own. These people live behind us, their backyard points to ours.

This woman was crazy and when my wife tried to become friends with her she came over high and made all these screaming threats toward her husband. We even found out they ripped down the fence to hang out with the prior tenants because they were friends. My landlord is now suing them for the fence and thankfully we found out that the tenants prior to the ones to the ones before us put a restraining order in place where come to find out they can't step foot on our property until December 2013. I still don't trust them and it was made clear that when my land lord told the police about the fence they said, oh her.

I frankly don't care what these people do in their own home (even though your kid shouldn't be witnessing it), but we both live inside a "drug free school zone" sign set as we both live inside of a block of an elementary school. Does that mean anything from a legal perspective or not. I know that we can have them tossed if they show up on our property, but given how crazy she was I don't trust that and was wondering if I have extra help against them just in case.